1. Field of the Invention
This invention relates to textile articles possessing antimicrobial properties and a method for their preparation.
2. Description of Related Art
Textile articles which have been treated to render such articles microbicidal to microorganisms coming in contact with the article are known in the prior art. Such articles include those made from paper, fibers, woven and non-woven textiles and like fabrics which are designed for use in environments such as hospitals, food processing plants, laboratories and other areas where maintenance of germ-free conditions is essential.
For example, U.S. Pat. No. 2,791,518 discloses a method of imparting microbicidal properties to articles such as textiles by immersing the article in a first aqueous solution containing a water-soluble basic nitrogen compound (ammonia) and a monovalent silver salt soluble in said solution, followed by a second immersion in a second solution containing a second salt capable of ion exchange with the silver salt such that a monovalent silver salt precipitate is formed within the article. The formed silver precipitate is sparingly water soluble and imparts microbicidal properties to the articles so treated.
Similarly, U.S. Pat. No. 5,271,952 discloses a method of treating fibers to render them electrically conductive as well as anti-bacterial comprising immersing the fibers in a bath comprising an aqueous solution of a source of divalent copper ions, a reducing agent, sodium thiosulfate and a source of iodide ions, whereby copper iodide is adsorbed into the fibers. Similar techniques for rendering fibers conductive and/or resistant to bacteria involving the use of copper compounds are disclosed in U.S. Pat. Nos. 4,410,593 and 5,458,906.
One of the main problems associated with the use of monovalent silver compounds such as the halides, phosphates or sulfates in such applications is that they are sensitive to ultra-violet light and are thus prone to discoloration after exposure to sunlight, with a gradual loss of effectiveness of antimicrobial properties. Also, many of these compounds are soluble or slightly soluble in hot water which diminishes the antimicrobial properties after only a few launderings of reusable fabrics containing them.
Another problem with respect to the use of copper compounds as interstitially precipitated antimicrobials such as described in the above U.S. Pat. Nos. 5,271,952 and 5,458,906 is that these processes do not readily lend themselves to inclusion in textile production lines. Textile finishing lines involve processes which take minutes and cannot readily accommodate precipitations which require lengthy immersion times of sixty minutes or more.
The main object of the invention is to provide a method of treating fibers and/or configurated textile products so that anti-microbial properties are imparted to them. Another object of the invention is to incorporate into said fibers and textile products a powerful anti-microbial based on an electron active molecular crystal analogous to the molecular crystal, tetrasilver tetroxide, which has been proven one of the most powerful disinfectants known to man.
Another object of the invention is to form a multivalent cobal oxide by interstitial precipitation.
Still another object of the invention is to enable rapid mass production of anti-microbial fibers and textile products.